Report - Agence canadienne d'évaluation environnementale

Assessing the risks related to the project
Regarding the worst-case scenario stemming from an intentional act, the 5-kW/m 2
isocontour would extend to the shore at cap Gribane, at cap Brûlé and to the south
shore east of île d’Orléans. However, there are no dwellings or other sensitive
community facilities in these sites within the 5-kW/m 2 isocontour. For the maximum
scenario in the event of accidents, the 5-kW/m 2 isocontour would never reach the
shore. Moreover, the proponent also specified that the distance between an LNG
tanker and île-aux-Coudres would be approximately 1.5 km on average, of more than
11 km for île-aux-Grues, and of more than 500 m from île d’Orléans (PR5.3.2, p. 3;
PR5.1, p. 3.117 and Figures A-42 to A-46).
Table 8 details a summary of the sensitive elements which would be located within
the 5-kW/m 2 limit of impact area in the sectors of the east point of île d’Orléans, of
Saint-Laurent-de-L’Île-d’Orléans and of Lévis-Beaumont. These elements are also
illustrated in Figure 8.
The proponent identified the sensitive elements in the built environment located within
the 1.6-kW/m 2 thermal radiation threshold. His analysis considered a scenario with a
breach of 750 mm, representing a distance of 780 m for this radiation level. According
to this assessment, these were the places where the 1.6-kW/m 2 isocontour would
make land and where the sensitive elements are: the east point of île d’Orléans, the
sector of Saint-Laurent-de-L’Île-d’Orléans and the south shore to the right of the jetty
(DQ99.1, p. 4 and 5). These sensitive elements are identified in Figure 8. The
distance for the accident scenario with a breach of 1,500 mm for a 5-kW/m 2 thermal
radiation limit would be approximately 820 m for the Qflex type LNG tanker. The
Panel was satisfied with this inventory, but it believes it appropriate that the proponent
complete the inventory of these elements by taking into account a 3-kW/m 2 thermal
radiation limit for a scenario involving a breach of 1,500 mm and a steady-state spill
pool fire, so that this information could be made available when planning emergency
measures.
138 Rabaska Project – Implementation of an LNG Terminal and Related Infrastructure